15 lines
200 B
Text
15 lines
200 B
Text
fmod FACTORIAL is
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protecting INT .
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op undefined : -> Int .
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op _! : Int -> Int .
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var n : Int .
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eq 0 ! = 1 .
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eq n ! = if n < 0 then undefined else n * (sd(n, 1) !) fi .
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endfm
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red 11 ! .
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